The present invention relates to a release film, a major utility of which is to protect and carry label stock until the label is put into use on an appropriate surface.
For many years labels have been prepared with a pressure sensitive adhesive applied to one side thereof. Obviously some means had to be provided to protect the adhesive surface in advance of applying the label to the ultimate surface to be labeled. A technique has evolved over the years by which the pressure sensitive adhesive surface is protected by bringing the adhesive surface into contact with a release layer which has little tendency to aggressively adhere to the pressure sensitive adhesive surface. Thus, a second film having a release surface is brought into contact with the pressure sensitive surface carried by the label and thus protects the pressure sensitive adhesive until the label is to be applied to its ultimate surface.
Release films can be manufactured separately from the label face stock. The release film is manufactured and then convolutely wound into roll stock, which is thereafter unwound and slit during the manufacture of release film of a particular width dimension suited for a particular label dimension. Often times the release film roll stock manufacturer sells the roll film to a different commercial entity which performs one or more of the follow-on steps leading to the ultimate release film-label combination for end use on a particular surface or product.
A problem which manifests itself during the manufacture of release film is the transfer of areas of release material to the back surface of the film. This transfer leads to printing problems during completion of the release film-label stock combination. After the release film is mated with adhesively backed label stock, the label surface is printed with the appropriate label indicia. This printing operation is a step which often occurs after the release liner and label stock has been mated and convolutely wound. If during winding and unwinding of the release film, release material is inadvertently transferred to the back surface of the release film, this unwanted transfer can, in turn, be transferred to the surface to be printed and the printing ink will not adhere to such surfaces. This condition, at this point in the operation, results in a costly rejection of the release film-label combination.
It is an object of the present invention is to present a release film, which will not transfer release material to any part of a label surface intended to be printed.